A thin film removing device and a thin film removing method are capable of removing straight parts of a thin film formed on a square substrate from corners of the substrate, and of suppressing the formation of mists. An approach stage 20 having flat stage plates 23 capable of being disposed substantially flush with the surface of a substrate M mounted on a support table 22 is positioned close to the substrate M mounted on the support table 22. Removing nozzles 30 jet a solvent toward edge parts of the substrate M and suck a solution produced by dissolving part of the resist in the solvent while the removing nozzles 30 are moved along side edges of the substrate M and the approach stage 20 disposed close to the substrate M. Thus, the removing nozzles 30 jet the solvent uniformly over the edge parts and corners of the substrate M and suck the solution without changing modes of jetting the solvent and sucking the solution. Consequently, straight parts of a thin film formed on the square substrate M can be removed from the corners of the substrate M, and the formation of mists can be suppressed.